Conventionally, with a so-called breakout cable, at one end of a cable is a connector capable of transferring data at a certain maximum transfer rate while at the other end of the cable are plural connectors each capable of transferring data at a transfer rate that is a fraction of the certain maximum transfer rate. For example, a single port of a network device may be connected with respective ports of plural information processing apparatuses by using a breakout cable.
According to a related prior art, for example, a switch between a computer and a storage apparatus manages relayed commands, and when detecting an obstacle, the switch concurrently transmits an error response to the computer and changes configuration so that subsequent commands are relayed along an alternate route. According to a further technique that is a Media Access Control (MAC) address table control method of a switching hub apparatus, a MAC address table is controlled according to a link state of an external apparatus connected to the switching hub apparatus. According to another technique, based on load information that indicates the load of each port allocated to targets that manage initiator commands from an external apparatus connected to a network, an instruction is given to change the allocation of the ports for the targets so that the load of ports becomes distributed. For examples of such techniques, refer to Japanese Laid-Open Patent Publication No. 2005-051335, Japanese Laid-Open Patent Publication No. 2000-151674, and Japanese Laid-Open Patent Publication No. 2006-079378.